header {
    width: 100%;
    height: 0.5rem;
    background-color: #1d6dff;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 0.1rem;
}

header .back {
    text-align: center;
    line-height: 0.5rem;
}

header .back a {
    height: 0.4rem;
    width: 0.4rem;
    font-size: 0.2rem;
    color: #fff;
}

header h1 {
    font-size: 0.2rem;
    font-weight: 900;
    color: #fff;
}

header .app a {
    display: block;
}

header .app a img {
    height: 0.34rem;
    width: 0.34rem;
}